Mr J. F. M. FLOYD was good enough to hand over to me for report some smears which he had made in British Guiana from the contents of Termite intestines. Prof. Silvestri, who was kind enough to examine some Termites taken from the same colony as those which furnished the material for the smears, identifies them as belonging to the species, Rhinotertnes nasutus Perthy, and it is probable that this is the host of the parasite described below.

A number of Cestodes collected from a hedgehog in Mesopotamia by Dr Boulenger were handed to me for identification. Examination showed them to belong to the genus Oochoristica. Five Cestodes [Hymenolepis erinacei (Gm.), Hymenolepis steudeneri V. Janicki, Davainea parva V. Janicki, Taenia valuta V. Linstow, and a Bothriocephalus Larva V. Janicki] have up to the present been recorded from this host. From all these, the present species is distinguished by its possession of numerous testes, situated posteriorly to the female organs. I therefore propose to form a new species for its reception and suggest for it the name Oochoristica erinacei. The key attached to the following description will serve to distinguish this new species from others of the same genus. I wish here to express my indebtedness to Dr Boulenger for placing his material at my disposal.

The status of Trypanosoma suis was held in doubt from the time it was first seen in 1905 until it was re-discovered and carefully studied in the Belgian Congo in 1954.

A description is given of the morphology of single and dividing forms of T. suis as seen in stained thin films made from the blood of infected pigs, and a selection of these is illustrated by line drawings. Briefly this trypanosome is short and stumpy with a free flagellum.

A biometrical study was made on 200 organisms, showing a normal length distribution with a range from 8·5 to 18·5μ, and mean = 14·43μ.

The monomorphism of the trypanosome is verified, and—because of its development in the salivary glands of Glossina—its systematic position as a monomorphic subgroup of the Brucei group is confirmed.

I am much indebted to Dr C. A. Hoare, F.R.S., for the loan of the blood films used in this study and for his interest in the work. I am also grateful to Professor P. C. C. Garnham for providing me with accommodation and equipment at the London School of Hygiene and Tropical Medicine.

Five species of acephaline gregarine parasites – Apolocystis pilosa Meier from Lumbricus castaneus, L. festivus, L. rubellus and L. terrestris, Monocystis arcuata Boldt from L. castaneus, Nematocystis gracilis Berlin (= N. anguillula var. gracilis) from L. castaneus and L. rubellus, Zygocystis cometa Stein from Allolobophora caliginosa and Z. eiseniae Loubatieres from Eisenia foetida – identified during the present work are new to the British record.

The characteristics of two other monocystids, N. lumbricoides Hesse and N. lumbricoides var. pilosa Meier are identical apart from the presence of short ectoplasmic hairs on the latter trophozoite's body. Since the presence of ectoplasmic hairs which are projections on the trophozoite's body is often utilized in gregarine speciation, the hairy and the hairless monocystids should be described separately.

Berlin (1924) identified N. anguillula var. gracilis from the seminal vesicles of Lumbricus terrestris, L. rubellus and L. castaneus. This trophozoite should have been described as a separate species, N. gracilis Berlin and not as a variety of a totally different species originally described by Hesse (1909) from a host, Pheretima rodericensis, a megascolecid oligochaete, not found in Europe.

The writer wishes to express his sincere appreciation to Dr Anne Terry for her advice and useful suggestions, and to Mr D. Etherington, the head of department, for his encouragements throughout this research period.

The mature egg and the acanthor of Moniliformis dubius have been redescribed with special emphasis on the features relevant to the locomotion of this larval acanthocephalan. The movements of acanthors have been analysed by the use of frame by frame study of filmed records of motile acanthors. Acanthors appear to use the same mode of locomotion for hatching, locomotion within the gut of the intermediate host and penetration of the host's gut wall. Movement is produced by a set of spiralled, longitudinal muscles in the body wall of the hind body and two rostellar retractor muscles. This musculature acts both directly on the body wall and indirectly by hydraulic effects via the hydrostatic skeleton of pseudocoelomic fluid. The spiny evertable rostellum and the backward facing spines of the hind body are the means whereby shape changes of the acanthor interact with the immediate environment to produce effective progression.

I should like to thank Professor D. Arthur for the provision of laboratory facilities, Dr D. W. T. Crompton for the initial gift of eggs of M. dubius and Mr R. D. Reed for invaluable assistance with microcinematographic technique. The work was carried out during the tenure of a Nuffield Foundation Research Fellowship.

Males of Nematodirus battus have a body wall composed of a longitudinally ridged cuticle made up of 8 layers, a hypodermis and a layer of longitudinal muscle cells which are divided into 4 sectors by the hypodermal cords. There is a characteristic cephalic inflation of the cuticle in both sexes. The structure of the body wall in the anterior half of the female is similar to that of the male. In the posterior half of the female the cuticle is not ridged and has 7 layers; the longitudinal muscles are reduced in number and the lateral hypodermal cords increasingly extend dorsally and ventrally along the length of the posterior part of the nematode and come to occupy most of the lateral sectors of the body. The possible significance of these modifications in the structure of the female nematode are discussed.

In mice infected with the intestinal flagellates Giardia muris or Spironucleus muris, together with the blood parasites Babesia microti or Plasmodium yoelii, there is a temporary decrease of flagellate cyst output coincident with the peak of the blood parasite infections, followed by a rapid return to normal levels. This decrease in cyst output is correlated with decreased numbers of trophozoites in the small intestine. The effect on S. muris is more marked than that on G. muris. Neither blood parasites has any effect on the total duration of the flagellate infection and the flagellates do not affect the blood parasites. In mice infected with G. muris or S. muris and P. berghei there is also a decrease in cyst output but this is less apparent than in infections with B. microti or P. yoelii because of the fatal nature of the P. berghei infection. It is suggested that the decrease in cyst output is probably due to changes in the contents of the small intestine or to non-specific immunological factors rather than to specific immunological changes.

Detailed descriptions are given of the larvae of the three species of British metastriatan ticks, with particular reference to the arrangement and dimensions of setae.

Schizont-infected red blood cells (SI-RBC) from Plasmodium berghei-infected mice contain between 2 and 10 times as much sialic acid as uninfected RBC from the same blood (99–550 μg/1010 RBC versus 33–65 μg/1010 RBC). Total RBC samples from infected animals containing up to 63% ring- and trophozoite-infected cells had identical sialic acid contents to purified RBC samples (of < 3% parasitaemia) from the same blood (52–64 μg/1010 RBC). We conclude that RBC containing immature parasites have the same sialic acid content as uninfected RBC from infected blood and that total cellular sialic acid increases during maturation to the schizont stage. Uninfected RBC from infected blood had 25–50% as much sialic acid as normal mouse RBC (33–65 μg/1010 RBC versus 126 μg/1010 RBC). There were no qualitative changes in RBC sialic acids, all RBC samples having 60–70% N-acetyl neuraminic acid, 30–40% N-acetyl-9-O-acetylneuraminic acid and 5–10% N-gly colylneuraminic acid. The quantitative changes we observed during infection must reflect changes in murine sialoglycoconjugates, as we have shown elsewhere that Plasmodia do not synthesize or contain sialic acids. Since the sialic acid composition of mouse serum glycoconjugates is quite different to that of the RBC fractions studied here, the quantitative data suggest that part of the sialic acids of the uninfected RBC has been transferred to SI-RBC. With higher molar ratios of periodate to substrate than generally used, we were able to radio-isotopically label normal murine sialoglycoproteins on SI-RBC and purified uninfected RBC from infected blood by the periodate/NaB3H4 method. Several new proteins were then tritiated with SI-RBC but these proteins may be intracellular and could even lack sialie acid.

GLP-1 (abnormal germline proliferation) is a Notch-like receptor protein that plays an essential role in pharyngeal development. In this study, an orthologue of Caenorhabditis elegans glp-1 was identified in Meloidogyne incognita. A computational analysis revealed that the orthologue contained almost all the domains present in the C. elegans gene: specifically, the LIN-12/Notch repeat, the ankyrin repeat, a transmembrane domain and different ligand-binding motifs were present in orthologue, but the epidermal growth factor-like motif was not observed. An expression analysis showed differential expression of glp-1 throughout the life cycle of M. incognita, with relatively higher expression in the egg stage. To evaluate the silencing efficacy of Mi-glp-1, transgenic Arabidopsis plants carrying double-stranded RNA constructs of glp-1 were generated, and infection of these plants with M. incognita resulted in a 47–50% reduction in the numbers of galls, females and egg masses. Females obtained from the transgenic RNAi lines exhibited 40–60% reductions in the transcript levels of the targeted glp-1 gene compared with females isolated from the control plants. Second-generation juveniles (J2s), which were descendants of the infected females from the transgenic lines, showed aberrant phenotypes. These J2s exhibited a significant decrease in the overall distance from the stylet to the metacorpus region, and this effect was accompanied by disruption around the metacorporeal bulb of the pharynx. The present study suggests a role for this gene in organ (pharynx) development during embryogenesis in M. incognita and its potential use as a target in the management of nematode infestations in plants.

Among a large collection of alcohol material of Danish fleas, belonging to the Universitetets Zoologiske Museum at Copenhagen and kindly sent to me for identification by Dr S. L. Tuxen, was a tube which not only contained the fleas Chaetopsylla trichosa Kohaut (6 ♂, 22 ♀) and Paraceras melis melis (Walker) (3 ♂, 30 ♀), but also a large number of the chewing louse Trichodectes melis (Fabricius). These female of Trichodectes melis, is firmly attached on the outside of the left mid-tibia by having its mandibles entirely surrounding the tibia (Fig. 1). The two insects have been mounted on one slide (which is incorporated in the British Museum collection of fleas at Tring) and the attachment of the louse to the flea is so firm that the act of preparation did not separate the two insects.

The daily rate at which a young lamb acquired keds from its mother was studied. Keds applied themselves closely to the skin of the lamb, many on the under, sheltered parts of the body. It is concluded that there was almost completely oneway traffic of keds from the ewe to the lamb. A fall in the rate of transfer of keds to the lamb was attributed to declining frequency of contact between the latter and its mother, associated with transition from a wholly milk diet to one in which pasture became of increasing importance. It was found that during the hours of darkness and some hours of daylight few, if any, keds were acquired by the lamb. Keds tended to accumulate on the lamb in greater numbers during periods of many hours of bright sunshine and little rain than those of few hours of sunshine and much rain. The running totals of keds acquired by the lamb more nearly paralleled the running totals of hours of bright sunshine than other meteorological factors. It is concluded that the connexion was indirect and that sunshine raised the temperature of the fleece of the mother in the regions directly exposed to the rays, causing greater numbers of keds to appear on the surface, so that the lamb was exposed to a risk of heavier infestation. At one stage of the experiment a greater proportion of the males than females transferred from the ewe to the lamb. This is explained in terms of there being a higher proportion of males in the hinder part of the body of the ewe, a region with which the lamb, in feeding, came more frequently into contact. The higher ratio of males to females in the posterior half of the lamb than in the anterior is explained by the more pronounced habit of males than females to migrate through the fleece.

The cestode herein described was obtained from the intestine of a Schokari Sand Snake which died on 16. xii. 1929 at the Zoological Gardens, Giza, after being 6 months in captivity. The material (Museum No. 1717) was placed at my disposal by Prof. Khalil for study in the Department of Parasitology.

Efficacious antimalarial drugs are important for malaria control and elimination, and continuous monitoring of their efficacy is essential. The prevalence and distribution of Pfmdr1 were evaluated in African migrant workers in Henan Province. Among 632 isolates, 13 haplotypes were identified, NYSND (39.87%, 252/632), YYSND (2.85%, 18/632), NFSND (31.01%, 196/632), NYSNY (0.47%, 3/632), YFSND (13.77%, 87/632), NFSNY (0.32%, 2/632), YYSNY (2.06%, 13/632), YFSNY (0.16%, 1/632), N/Y YSND (1.90%, 12/632), N Y/F SND (6.17%, 39/632), N/Y Y/F SND (0.47%, 3/632), YYSN D/Y (0.16%, 1/632) and N/Y FSND (0.79%, 5/632). The highest frequency of NYSND was observed in individuals from North Africa (63.64%, 7/11), followed by South Africa (61.33%, 111/181), Central Africa (33.33%, 56/168), West Africa (28.94%, 68/235) and East Africa (27.03%, 10/37) (χ2 = 54.605, P < 0.05). The highest frequency of NFSND was observed in East Africa (48.65%, 18/37), followed by West Africa (39.14%, 92/235), Central Africa (26.79%, 45/168), South Africa (22.65%, 41/181) and North Africa (9.09%, 1/11) (χ2 = 22.368 P < 0.05). The mutant prevalence of codons 86 and 184 decreased. These data may provide complementary information on antimalarial resistance that may be utilized in the development of a treatment regimen for Henan Province.

Hosts face mortality from parasitic and environmental stressors, but interactions of parasitism with other stressors are not well understood, particularly for long-lived hosts. We monitored survival of flour beetles (Tribolium confusum) in a longitudinal design incorporating cestode (Hymenolepis diminuta) infection, starvation and exposure to the pesticide diatomaceous earth (DE). We found that cestode cysticercoids exhibit increasing morphological damage and decreasing ability to excyst over time, but were never eliminated from the host. In the presence of even mild environmental stressors, host lifespan was reduced sufficiently that extensive degradation of cysticercoids was never realized. Median host lifespan was 200 days in the absence of stressors, and 3–197 days with parasitism, starvation and/or DE. Early survival of parasitized hosts was higher relative to controls in the presence of intermediate concentrations of DE, but reduced under all other conditions tested. Parasitism increased host mortality in the presence of other stressors at times when parasitism alone did not cause mortality, consistent with an interpretation of synergy. Environmental stressors modified the parasite numbers needed to reveal intensity-dependent host mortality, but only rarely masked intensity dependence. The longitudinal approach produced observations that would have been overlooked or misinterpreted if survival had only been monitored at a single time point.

A partial cDNA sequence was obtained from the human blood fluke, Schistosoma mansoni using a signal sequence trap approach. The full-length cDNA was cloned and termed Sm-7TM. The corresponding open reading frame had 7 membrane spanning domains and shared identity with a small, novel group of seven transmembrane (7TM) receptors from vertebrates and invertebrates, including the human ee3 receptor – a heptahelical protein implicated in neuronal signalling. Phylogenetic analysis of this novel family showed that the Sm-7TM ORF formed a clade with exclusively invertebrate sequences. Based on topology modelling with ee3, Sm-7TM was predicted to possess an intracellular C-terminal tail, which was expressed as a soluble thioredoxin fusion protein (Sm-7TMC) in Escherichia coli and purified using metal ion-affinity chromatography. A polyclonal antiserum against this domain was used to detect Sm-7TM in detergent-soluble parasite extracts and to immunolocalize the receptor to the tegument of adult S. mansoni.

A full understanding of the immune system and its responses to infection by different pathogens is important for the development of anti-parasitic vaccines. A growing number of large-scale experimental techniques, such as microarrays, are being used to gain a better understanding of the immune system. To analyse the data generated by these experiments, methods such as clustering are widely used. However, individual applications of these methods tend to analyse the experimental data without taking publicly available biological and immunological knowledge into account systematically and in an unbiased manner. To make best use of the experimental investment, to benefit from existing evidence, and to support the findings in the experimental data, available biological information should be included in the analysis in a systematic manner. In this review we present a classification of tasks that shows how experimental data produced by studies of the immune system can be placed in a broader biological context. Taking into account available evidence, the classification can be used to identify different ways of analysing the experimental data systematically. We have used the classification to identify alternative ways of analysing microarray data, and illustrate its application using studies of immune responses in mice to infection with the intestinal nematode parasites Trichuris muris and Heligmosomoides polygyrus.